Everyone is at risk for eye damage from the sun. The same harmful rays that damage skin can also increase the risk of developing eye problems. Some of the long-term effects of UV radiation happen slowly and painlessly. Research has found that UV and other sun rays are involved in many of the serious eye disorders people experience today.
In the short-term, people who spend long hours on the beach or in the snow without adequate eye protection can develop photokeratitis, sunburn of the cornea, which can cause temporary loss of vision. The sunlight's reflection off of snow, sand or water, further increases a person's exposure to solar radiation.
Most people are unfamiliar with the sensitive nature of their eyes. According to optometrists and ophthalmologists, there are three surfaces within the eye that can be adversely affected by sunlight—the cornea and conjunctiva (snowblindness and pterygium), the lens (cataracts), and the retina (eclipse blindness and macular degeneration). These surfaces perform different functions that work together as the backbone of the eye structure. In addition, the eyelids are at risk of developing skin cancer from UV exposure.
To protect eyes from both short and long-term damage, people should wear sunglasses that block the sun's harmful rays. Pricey sunglasses or glasses with a dark tint don't always offer more protection. People should look for labels that specifically say the glasses offer 99 percent to 100 percent UV protection. Some eye-care professionals can also test the UV protection level of sunglasses for a customer.
Tint of the sunglass lens does play a role in the amount of protection. Amber or brown lenses, for example, may distort colors. However, they will attenuate most or all of the shortest wavelengths in the visible spectrum, which may contribute to macular degeneration in the retina.
The style or frame coverage of the sunglass also affects the amount of scattered or reflected harmful radiation, which can reach the eye without transmitting through the lens. Wrap-around sunglasses, which fit close to the face offer more solar protection than small frames.
People who wear contact lenses that offer UV protection should still wear sunglasses for total eye protection.
Children should also wear sunglasses that indicate a high UV-protection level, and not toy glasses without a label. Polycarbonate lenses are generally recommended for children because they are the most shatter-resistant.
The prior art has provided numerous specific configurations of children's sunglasses. None, however, have proven to be entirely satisfactory. Some prior art children's sunglasses are difficult to construct, expensive, and so uncomfortable to wear that children refuse to wear them. Moreover, some children's sunglasses are not suitable for very small children or infants, as the frames and other parts are relatively rigid and subject to breaking, which products have relatively sharp edges that can injure an infant or small child, or small parts which may break free causing injury.